Spring-reaction neutralizer



March. 24, 1931. mb oss E 1.797.719

31 mm REACTION NEUTRALIZER' Filed Nov; 1'7, 1927 3 Sheets-Sheet 1-l'nVen 23ers 6RosvENoRA L6R0ss fioDER/c M. CRoss ikq M4 (221M A TTORNEY5 March 24, 1931. ca. M. CROSS ETAL 1,797,719

SPRING REACTION NEUTRALIZER Filed- Nov. 17. 1927 s Sheets-Sheet 2 4Invenvqrs 6RosvENoR/M. cRoss Fromm/0M. CROSS A TTORNEYS March 24 1931.G. M. CROSS ET AL 1,797,719

SPRING REACTION NEUTRAL-IZER Filed Nov. 17, 1927 3 Sheets-Sheet 5Inventors RosvzNor? M GRO65 RODER/c: M. Gnoss fi ul G m A TTORNE YSPatented Mar. 24, 1931 UNITE raves ATENT OFFICE GROSVENOR M. CROSS ANDBODERIC M. CROSS, MINNEAPOLIS, MINNESOTA SPRING-REACTION NEUTRALIZER IThis invention relates to an improved device or mechanism adapted foruse generally to neutralize the reaction of springs or yieldableelements such, for example, as are used in the construction ofautomobiles, to cushion the loads carried thereby, the purpose of thusneutralizing the reaction of the springs being to prevent shocks andjolts from being transmitted to the body of the vehicle.

An object of this invention is to provide a device adapted to beconnected between two elements separated or connected by a yieldingmeans such, for example, as a spring, the device being so constructedthat it will allow freedom of initial movement of the yielding means in.either direction from a normal or neutral position, that is, theconstruction of the device is such that it will offer substantially noresistance to the further separation, or the bringing closer together ofthe two movable elements, no matter from what cause the elements aremoved; and while the elementsare returning towards their normal orneutral positions, the device will tend to oppose this return movementwith a force which is at all points in the return movement,substantially equal to the difference between the normal pressure ortension of the yielding means and its pressure or tension due to its 30deflection from normal, that is, the opposing I force may, be soadjusted as to be substantially equal at all times, to theamount bywhich its pressure or tension is greater or less than its normalpressure or tension, when the elements are in their normal relativepositions.

A further object is to provide a hydraulic spring reaction neutralizeradapted to be connected between the frame members of a ve- "hiclechassis and the axles thereof, said neutralizer being so designed andconstructed as to substantially counteract the reactive forces of theusual springs interposed between r the chassis frame and the vehicleaxles, that is, when the springs are either compressed or expanded, as aresult of the vehicle passing over a bump or a depression in theroad-way, the neutralizer will act against the return of the springs totheir normal positions, and -will neutralize such movement with theresult that when the wheels encounter a bump or depressionintheroad-way, practically no jolts or shockswill be transmitted to thevehicle body.'

A further object is to provide a device for opposing the reactive forcesstored in the Vehicle spring as result of its movement in eitherdirection from a normal position, which comprises a mechanism adapted tobe actuated by movement of the springs from a normal position, to causean opposing force to be temporarily stored in the device, which acts tooppose the reactive forces temporarily stored in the vehicle spring; andthe opposing force being greater at large and lesser at smalldeflections of the springs from normal, and the mechanism being soconstructed that I the opposing forces temporarily storedtherein tocounteract the reaction of the springs,

may be adjusted to obtain the desired degree of opposition to thereactive forces of the springswhen returning to normal positions, whichwill cause the travel of'the body to follow substantially a straightline; that is, the line of travel of the body will not be noticeablyafiected by the wheels encountering bumps or depressions in the roadsurface.

A further objectof the invention is to provide a spring neutralizercomprisinga casing adapted'to be secured preferably to the side frame ofthe vehicle chassis, and having a rock shaft mounted therein to one endof'which a lever is connected, which lever has a connection with thevehicle axle, and a spring-actuated plunger being mounted within saidcasing for circulating the fluid therein, said plunger having acam-shaped head adapted to be engaged by an arm secured to therockshaft, the arm being so positioned upon therock shaft that-when thevehicle spring is in neutral position, the plunger will bejdepressedagainst a coiled compression spring which constantly tends to urge theplunger upwardly so that when the arm is oscillated in either directionfrom normal, by compression or expansion of the vehicle springs, theplunger will be moved in a direction towards the rock shaft, therebycausing the fluid to flow into the lower por- 1 tion of the casingthrough a valved opening;

(iii

and when the arm COD'IIHQIICGS return movement, as a result of thereaction of the vehicle spring, the plunger will be forced downwardlyagainst the fluid confined in the lower portion of the casing, forcingthe fluid beneath the plunger through a series ofsmall ducts normallyclosed by an annular valve seated under heavy spring tension, thetension of this spring being such that the mech by'a camdevice,'whenithe=movable elements areimoved in either directionfromanornial.

position; to. provide such; a device comprising; aplunger andi-va-lvemechanism adapted to: controLcirculation of: a fluid therein,:said valvemechanism permitting substantially free circulation of the fluid: inonedirection, but restrictingthe return flow of fluid in the oppositedirection; toprovide an-tiefriction. meansifor' engaging-thecam'surfaces of the plunger to. minimize, friction; and; to, pro

vi-desuoh. a device of comparatively simple and inexpensive constructionwhich will be substantially;fool=proof andpositive in performance andmay be manufactured at a minimum cost. f

The particular object ofthe invention, therefore,. is to provide aspring reaction neutralizer, more particularly adapted-for use inconnection: with vehicle springs for neutralizingthe reactive forcesstored therein when in position other-than norma l Other objects oftheinvention will appear from. the following description andaccompanying. drawings and will be pointedout in the annexedclainis. sIn the accompanyingdrawings; there has been, disclosed a structuredesigned to carry out the Various r objects of: the; invention,-. but

it istoabe understood that-,theinvention not confined tothereXact-featuresshown as various. changes may be made within the scopeofthe;claimsfiwhicli-follow V p In the accompanying. dra wings formingpart ofthis specification Figure: I is a. sideelevational VIBW'Y'OI' aportion of a motor'veliicle showingthe iin-V proved neutralizen mountedthereon;

Figure -2isi a vertical sectional; View, p artial-liy in elevation,showing the'pa rtsain nor= mal or neutral-position;

Figure 3" is ahvertical sectionalwiew on 1 of a connecting rod 24, thelower end of which the line of Figure 5, showing infull and dotted.linest-hepositions assumed bythe rocker arm and plunger, when thevehicle spring is respectively compressed and expanded, the arrows inthe lower portion of the figure indicating the flow of fluid uponmovement of the plunger in a direction towards the rock shaft;

Figure t is a detailed'sectionalview of the lower portion ofFigure 3,the arrows indicating the flow of the fluid when the plunger isreturning to normal against fluid pressure;

Figure 5 is an elevational-view'of-the device partially broken away tomore clearly show the connection between the rocker arm and the plunger;

Figure 6 is a plan view of the adjusting nut provided for varying-thetension in the neutralizing spring; and

Figure 7 is a perspective view of the spring member provided for closingthe annular check valve controlling fluid flow into the lower portion ofthe casing.

The-novel sprin reaction neutralizing device featured in" this inventionincludes a casing comprising upper and lower sections 2' andy3',respectively, the lower section 3 being secured to the upper section bymeans offaflanged nut 4, received in threaded engagement with'theuppersection 2 and having' an inwardly turned flange 5 engaged withanoutwardly turned flange 6, provided upon the upper edgegof the lowersection 3. Anau-Xiliary fluid reservoir 7 may. be providedin the upperportion of; the casing as shown in Figure 5. This reservoir has ademountah'le cap 8 which may be removedto permit the introduction offluid, such; as oil; 'ato the casing. In operation, thecasing isfli-led'w lrfluidl as indicated in Figure 3.

A-roclir-slraftfi is mounted in:bushings l1 and; 12, seated respectivelyin bores 13' and 141 as show-nin- Figure 5. A suitable packing- 16 isinterposed between oneend of the'bushing 12 and-a nut: 'to preventleakage of oil around the shaft .A lever-17. is mounted upon the rock:shaft 9; and is prevented from rotation thereon by means of splines 18.A lock screw 20 secures the lever 17 to the shaft. The inner end of therock-shaft 9 is preferably smaller indiameter than that portionthereofw'vhichtraverses the packing nut 15. Axial movement of the rockshaft is prevente'das a result of the hub of the, level 17 engaging oneend of thebushing 11, the other end of-which is seated against thebottonrofit'he bore 13 as shown-in Figure 5-. A spacingcollar' 21has-one end seated against the OPPOE-iltfi side oftho lever 1'7 and iother end against shoulder 19, provided'in the, casing member 2.

An 22 is terminally secured tothe rock.

shaft 9, exteriorlyof the casing, and preferably.has a ball-andsocketjoint 23 of ordinary constructlon, connecting it to'one end is.suitablyconnectedto the'ax-lc of the vehicle or to the non-flexingportion of the vehicle spring 25. Figure 1 illustrates a manner ofsecuring the device to the vehicle and, as here shown, the upper portion2 of the casing is secured to the front hanger 26 of the vehicle chassisby means of bolts 27 Thus, when the spring 25 flex-es, as a result ofthe wheel passing over irregularities in the road surface, the arm 22will be oscillated to rock the shaft 9.

An important feature of this invention resides in the construction ofthe means provided for controlling the circulation of the fluid withinthe casing, each time the arm 22 is oscillated, as a result of thespring 25 being expanded or compressed. Such means consists of a plunger28 reciprocally mounted in a cylinder 29, and preferably having anenlarged flanged head 31 received in threaded engagement with the lowerportion of the casing member 3, as shown in Figures 2 and 3. Thecylinder 29 is open at each end. The plunger 28 has a bore 32 adapted toreceive a compression spring 33, the upper end of which is seatedagainst the bottom of the bore 32 and its lower end against the bottomof the casing member 3. This spring constant-ly urges the plungerupwardly.

The plunger 28 has a forked head 34 provided with cam faces 35, one ofwhich is constantly engaged with one end ofa stud 36 adapted to rollthereon. This stud is rotatably mounted in a suitable anti-frictionbearing 37 mounted in the lever 17. The stud 38 has a reduced centralportion 38, tightly fitted in the bore of the roller bearing 37. Theopposite end of the stud 36 is reduced in diameter to receive a sleeve39, secured to the stud by means of anut 41, terminally mounted upon thereduced portion of the stud, as shown in Figure 5. The inner race of theroller bearing 37 is clamped between the shoulder 10 provided on thestud 36 and the sleeve 39, thus securing the stud to the inner race ofthe roller bearing so that the enlarged end of the stud and also thesleeve 39 may roll upon the cam faces35, when the lever 17 isoscillated. The diameters of the enlarged end of the stud 36 and thesleeve 39 are identical. The swinging end ofthe lever 17 is received inthe slot 42 provided in the head of the plunger, between the two camfaces 35. (See Figure '5.)

The valve mechanism employed in this novel neutralizer is best shown inFigures 2, 3, and 4. By reference to Figure 3, it Wlll be noted that theinterior of the casing is divided substantially into two chambers, an

upper chamber 40, and a lower chamber '43. The lower chamber 43 isdefined by the bottonrwall of the casing member 3, and the lower ends ofthe cylinder 29 and plunger 28. The upper chamber 40 is defined by thewalls of the lower casing member 3, the exterior of the cylinder 29 andthe upper portion of the plunger 28. In Figure 2, the leverlZ andplunger 28 are shown in normal positions, or in the I positions assumedwhen the vehicle spring 25 is in normal or neutral position. When thevehicle spring is compressed, the arm 22 will be moved upwardly tocausethe lever 17v to assume substantially the position shown in fulllines in Figures 3, wherein it will be noted that the compression spring33 has caused by the plunger 28 to be moved upwardly, therer by causingfluid to circulate fromthe upper chamber 40 into the smaller chamber-43.

The valve mechanism provided for controlling the circulation of thefluid between the twochambers'consists of an annular ring 44, mounted inthe lower portion of the member 3 of the casing beneath the head 31 ofthe cylinder 29; and a sleeve 45 movably mounted upon the exteriorof thecylinder as shown. A series of fluid ducts 54 are provided in thecylinder head 31 adapted to establish communication between the twochambers. These ducts are normally closed by the ring valve 44,yieldably held in closed position by means of a spring member 46, shownin Figure 7. A similar series of fluid ports 47 are also provided in thecylinder head 31, and these are preferably arranged in a circle closerto the bore of the cylinder and positioned tohave their upper'endsclosed by means of the lower end of the sleeve valve 45, as shown inFigure 3. The upper discharge ends of the ports 47 communicate with anannular groove 50, provided in the cylin} der head 31. This annulargroove is adapted to be closed by the lower end ofthe valve sleeve 45 asshown. An annular flange 48 is provided on the sleeve 45 against whichone end of a compartively heavy compression spring 49 is seated. Theother end of this spring is seated against an adjusting nutbl,

received in threaded engagement with the upper end of the cylinder 29and having'a key 52 engaged therewith and with the bore provided in thelower portion of the upper casing member 2, as shown in Figure 2. Thekey 52 prevents the'adjusting nut 51 from relatively rotating withrespect to the casing member 2. To adjust the tension of the spring 49,the flanged nut 4 is loosened, after which the lower casing member 3 maybe relatively rotated with respect to the upper casing member 2, therebycausing the cylinder to be relatively rotated within the nut 51, withthe result that the distance between the flange 48 and the lower face ofthe packing nut 51 is varied, thus changing the tension of the spring49. A' drain plug 53 is preferably provided in the bottom of the casingmember 2. Two tension springs 49 are preferably employed. These areconcentric and of the same diameter and are arranged with their coilsalternating. of the two springs are preferably bent up- Thev upperterminals 55' wardlv': and seatedin 1 apertures 56; provided in'the nut51.; The nut 5l also has-itsperipherynotchedas shown in. Figure 6 toprovide fllllClTCl'lC'tll ating passages.

Operation Inoperation, the entire device'is filled witha fluid such asoil, the auxiliary oilj chamber 7 being supplied with fluid as desired,to take care of expansion or contraction of: the fluid, due totemperaturechanges. A vent 57 is provided inithe capS defining-the upperwall of the. chamber 7.

Then the vehicle wheel engages an irregularity. or a bump intheroad-way, causing the vehicle spring to compress, the arm 22' will::beoscillated from-the full line position shown/in Figure 2 to the fullline position shown inpFigure 3, thereby rocking the shaft 9. andcausing,thelever 17 to be movedfrom the position showniin Figure 2to the full;line position shown, in Figure 3. Such movement ofthelever 17. permitsthe compression spring 33 to move the plunger. upwardly, the cam faces35ikeeping incontact' with the head ofthestud 3.6 and the sleeve 3.9;.As-the plunger 24. rises, a slight vacuum occurs .in the chamber 43, andatmospheric pressure forces the; fluid in the upper chamber throughztheducts;

; 5d and into. thechamber, the Valve ring: 44

being unseated, asshown inFi ure 3, by the pressure of the. fluidactingthereagalnst. Thus, the lower. chamber-.43. willbe kept: full offluid re ardl'ess of-the movement of the plunger. 28. It isobviousthatthe action. above. described, offers noimpedance to the movementofthe vehicle. axle under thebody so longas it continues towards-thebody; that. is, asfthe two.movable-elements.in thisinstance, the vehicleaxle andthe-ch-assis frame members, are movedtowardsieaohiotherfrom:their normal: positions, .the device. ofi'ers :no impedance. tothatmovement. As the wheel drops beneath the body. or into: a depression inthe road surface, the action is similar, the lever 17', however,swinging to thedotted. line position shown in Figure 3, Themovement ofthe arm 22- w-ill also bein theopposite direction, as indicated by thedotted lines in Figure 3. hen the par-ts are thus positioned,

' it will be noted that the stud 36 and sleeve 39 will be in contactwith the cam faces 35 at points theother side of the vertical. Thus, itwill be seen that the free travel of the.

" plunger 28.will be in the samedirection or upwardly, regardless ofvwhether the lever 17 is moved from normal to the full or the dotted linepositions shown in Figure .3. It, will benoted that the device willpermit the movable elements such, for example, as the vehicle chassisand'v'theaxle, across which it isconnected, to be moved in;eithendirection away from, normal position,,4that, is, itpe-rmits a freeinitial deflection of the yielding-connection from its original degreeof deflection.

When the parts have reached the positions indicated inwfnll-lines inFigureS, the exe cessive pressure or reactive force present in thevehicle spring resulting-from its compressed conditiom tends toreturnthe vehicle.

axle to. its normal position, thereby exerting a, force against theouter end of the arm 22 tending to move it downwardly from the full lineposition shown in Figure 3 to the full line position shown in Figure 2.In order to move in this direction, it is obvious that the plunger 28must be forced downwardly as a result of the stud 36- and sleeve 39acting against the camfaces 35, as the lever 17 returns to its normalposition, shown in Figure 2. Such downwardmovement of the plunger-28will causethe latter: to force the fluid into the chamber--10, causingthe sleeve valve 45 toibe opened against the pressure of the spring -19,thus permitting fluid to flow from the lower into the upper chamber, asindicated bythe arrows in Figure 4. The force-necessary to. force the.plunger 29 downwardly, is exertedbythe-stud 36. andnsleeve 39 againstthecam; faces 35; and hence must beexerted between body and axle. It isobvious, there-- fore, that this force opposes the return move mentofthebody and axle to their normal relative-positions.

The action of the plunger and valve mech-. anism,whe-n. the armi22 ismoved from the dotted line position shown in Figure 3 to the full lineposition shown in Figure 2, is practical-l-y identical, to. its actionor operation, when the arm 22 moves from. theful-l line positionshown inFigure. 3 to its normal posi tion. This. will readily be seen when it isunderstood that the return movement of the arm 22from either of thepositions shownin Figure 3,.to'i-ts normal position shown in. F ig.. ure2, cannot be effected without forcingthe plunger downwardly, whichmovement is 01)? posed'by the action of the spring 49 tending to retainthe sleeve valve 45 in closed position. A back pressure is exertedagainst the return movement of the arm 22 in either direction, throughthe cam faces 35, stud .36 and slee-ve39; lever 22, lever 17, shaft 9,and the connection: 24 between body and axle; thereby opposing theirreturn movement to normal relative positions. Hence, the device will,when connected between two relatively movable members connected by ayielding connection, allow free initial movement of said members. ineither direction from a normal position, either closer together orfartherapart; and, conversely, it will also oppose the returnmovementsof said movable members towards their normal positions from eitherdirection.

The magnitude of the force opposing the. return movement of the movableelements, such as vehicle body and axle, at any given .plungerwith suchforce that point, is determined by the following factors; the lengths ofthe arm22 and the connection 24, and the angles at which they areoperated from their connection with the vehicle axle; the diameters ofthe head of the stud 36 and the sleeve 39; the shapes of the cam facesthe effective areas of the plunger and the valve sleeve 45, and thepressureof the spring 49.- For the purpose of explanation, it will beassumed that all of these are constant with the exception of the camfaces 35 and the size of the spring 4-9.

The shapes of the cam tially determine the ratio of successiveincrements of the opposing force to successive increments of deflectionof the vehicle spring, whereas, the pressure of the spring 49 willdetermine the exact amount of the opposing pressure; that is, the ratioof the amount of vertical travel of the plunger during an elementaryunit of travel of the axle beneath the body, to the amount of that axletravel, determines the mechanical advantage or lever age of the plungervover the axle during that amount of travel. In other words, the camfaces 35 act as a variable leverage factorbetween the plunger 28 and thevehicle axle. Thus, almost any relationship of leverages from point topoint can be obtained bysimply varying the shapes of thecam faces $5.The pressure of the spring 49 together with the effective areas of thesleeve valve and the plunger 28 determine the upward force of theplunger; and this force multiplied by whatever leverage the piston hasover the axle at any given point of travel, determines the exact valueof the opposing force exerted by the neutralizer between body and axle.

Thus, by properly designingor shap ng the cam faces 35, and properlyproport oning the lever 17 and arm 22, with a constant velocity ofinitial axle rise beneath the body, the plunger can be made to travelWitllllnlformly accelerated motion that 1s from zero velocity at itslowest point to maximum at its highest, thereby givin an even change ofleverage between the plunger and theaxle, the leverage'being at alltimes proportional to -the degree of deflection of the veh cle spring,and therefore to the amount by which the pressure of the spring 15greater or less than normal. Hence, if the upward force on the plungeris sufficient exactly to oppose the amount by which the vehicle spring1s greater or less than normal at any one point, it will be so at allother points, as the leverage of the plunger on the axle changes wlththe force desired. V

As a result of the adjusting nut 51 being mounted for relative verticalmovement within the casing, the tension of the sprlng 4.9 may be variedto give the desired pressure, that is, its tension may be adjusted sothatit will oppose the returnmovement of the faces substanthe apparatus,

as a whole, will oppose the return movement of t-he vehicle spring witha force at all points substantially equal to the difference between thenormal pressure of the vehicle spring and its pressure at these pointsdue to sure'is not directly proportional to the de gree of itsdeflection, the cam faces 85' may be changed or altered to fit the newconditions and to give always the proper leveragesif it is desired tooppose with pressures not equal to but proportional to the amount bywhich the pressure of the yielding means is greater or less than normal,th-ecam faces will remain unchanged, it being only necessary to changethe pressure factors acting on the plunger, namely, the tension of thesprings 49, together with the fluid areas involved. To obtain otherdesired forces, the shapes of the camfaces 35 will be altered to fit theparticular case. It is obvious that any downward curve of these camfaces, or even a horizontal flat surface, will produce forces at theaxle greater at large deflections of the spring and lesser at small. Theother forces attainable by varying the shapes of thee-am faces 35, areonly limited by the curvature of the head of the stud 36 and the sleeve39, which will not allow too great a sudden change of angle, and thevarious other simple mechanical factors involved.

From the foregoing, therefore, it will be. seen that the construction ofthis novel spring reaction neutralizer is such that it may be readilyadapted for nsein connection with two movable elements having a yieldingconiection between them, to substantially oppose the reactive forcesstored up in such yielding connection after deflection and when tendingto return to normal position, or it may be made to give opposing forcesnot neutralizing but of almost any value desired.

Vi e claim as our invention:

1. A device for opposing the reactive force in a spring elementconnecting together two relatively movable members, comprising casingadapted to be securedto one of said members, a rock shaft in said casinghaving an operative connection with the other of said members, fluidchambers in said casing, an inelastic fluid therein, a valve mechanismbe tween said chambers, a plunger for circulating the fluid between thechambers, head on said plunger having an off-set portion, and means onthe rock shaft adapted'to engage said off-set portion and depress theplunger when said shaft is rocked.

2. A device for opposing the reactive force ina spring elementconnectingtogether two relatively movable members, comprising a casingadapted to besecured to one of said members, a rock shaftdn said casinghaving all Q whensaid sh ait is an operative coi'ine'etionwiththe otherof-said 1nembe'rs,f fluid chambers in said easing-an inelastic fluidtherein, a valve mechanism between said chambers, a plunger forcirculating the fluid between the chambers, ahead tially at right anglesto the axis oi-said plunger and being adapted to engage the offsetportion on-the plunger head, said oliset portion causing the plunger tobe depressed farther when said plunger-actuating means is at one end ofits movement'than when said means is at the opposite end of itsmovement.

3. A'dev-ice for opposing the reactive force ina SPIlTl'g'OlelllGlltconnecting together two relatively movable members, comprising a casingadapted to be secured to'oneot said members, a rock shaft in said casinghaving an operative connection with the other of said members, fluidchambers in said casing, an inelastic'fluid therein, a valve mechanismbetweensaid cha-mbers,'a plunger for-circulating the flu-id" between thechambers, a head 011 said'pl'unger having an oil -set portion at one endthereof and means on said rock -shaft moun'ted fornwinging movement andadapted to 'engagesaid off-set portion whens'aid means is positioned atone side of the plunger, whereby thephmger will be depressed agreaterdistance than when said actuating means is positioned at the oppositeside of the plunger axis; said valveniechanism being adapted to restrictthe flow of fluid, in one direction, whereby the force required toreturn the plunger to normal position, will oppose'thereactive forcestored in said spring element.

4;. A device for neutralizing the reactive force in a springeleinentconnectin'g together two relatively movable members, comprisinga casing adapted 'to' be secured to one 'ofsaid members, a rock sha'ittinsaid'caling havin an operative connection with theothe'r of'saidmembers, fluid chambers in said casing, an inelastic fluid therein, avalve mechanism between said chambers,

chambers, said plunger h aving a"can 1-shaped head provided'with an'ofl-seit portion, and means on said rock shaft engageablewith said headtoc'a use said plunger to beactuated 'onthe plunger head causingthepluu'ger to "be de' re'sised "a meter "distance'when saidplungenaetuating means is atonee'ndof Its "relatively movable-member's,-g a easing adapt'ed "to be-secured to one "of said movementthanvvhensaid means is 'a t"theend of its movement, whereby theoperation of said device may be controlled.

A "device foriieutralizing the reactive cejmasprm ei n ent'eonneenng'to'*mem bers, a' rock shaft in a spring-actuated 1 plunger forcirculatingthe fl'u'id between the rocked, the off-set portion members,a rock shaft'insaid casing having 1 an operative connection with theother of said 1nembers,;fluid'chambersin said casing, an inelastic fluidtherein, a valve mechanism between said chambers, a spr'ing ac'tuated'plun'ger for circulating the fluid betweentihe chambers, said plungerhaving a cam-shaped head provided with an off-set portion, and means onsaid rock shaft engageable with said head-to cause said plunger to beactuated when said shaft is rocked,-"said valvemechanism permitting freemovement of said plunger from normal position"andrestricting its returnmovement, and the elf-set portion on the plunger head causing theplunger to be depressed a greater-distance WllQHSfllCl plunger-aetuatmgmeans IS KIt' one end of its IHOVElll'GIlt than when said means is atthe other end of its movement, and'w hereby the operation of the devicemay be controlled.

A-devicefor opposing the reactive force in a springelement connectingtogether two relatively movable members,comprising a casing ada pted'tobe secured to one of said members-a ro'c'k shaft said casing having an-operativ'e coi-inect-ion wit'h the other ofsai-d mein ers, flnidehambers in said casing-aninelastic fiui'd there'i-n, a valve mechanismbetween said chambers, a cylinder in the easing open at both ends, s sj'n-ing-act'uated plunger "operable in said cylinder and "tending to movein a direction towards said constantly rock shiifhtheends of -saidplunger being adapted to project beyondthe-en'ds of the cylinder, meanson said rock 'shaft engag'eable with the 'plui-iger to controli-ts'movement, said valve mechanism being adapted-torest rict the 1 flowor fluid to retard the return movementof the plunger, and means for ad3ust i-ng said valve mechanism.

7. A de'v-icefor opposing the reactive "force in a spring elementconnecting together two relatively movable members, comprising a casingadapted to be secured to one of said said casing having an operativeconnection with the other of said members, fluid chambers in saidcasing,

an inelastic fluid therein, a valve mechanism between said chambers,acyh-nder in the casing open at both ends, a spring-actuated plungeroperable in said cylinder andconstautlytend'ing to move in adirection'to- "wards said rock shaft,-the ends of'said plungerbeingadapted topr'oject beyondthe endsof thecylinder, means on'said rockshaft engag'eabl'e with-the plunger to controlits-movement, said valvemechanism beinga'dap'tedto *res't'rict the flow of-fluidto retardthereturn "inoi ement of the plunger, and-means exteriorly' offsaichde'vice f r-adjustin said valve mechanism, to varytheforc'erequired v id pl'unge'rto norm'ahposition.

V 8. A dev ce foro'p'posing the reactive "force in-a spring elementconnecting-togetherewe relatively movable members, comprising a in onedirection, a cylinder in said casing, a plunger operable in saidcylinder for circulating the fluid between said chambers, meansconstantly urging said plunger in a direction towards said rock shaft,an irregularly shaped cam on one end of the plunger, means on said rockshaft engageable with said cam to cause actuation of said plunger, whensaid members are moved towards and-away from each other, and a portionof said casing being relatively movable to adjust the operation of saidvalve mechanism.

9. A device for neutralizing the reactive force in a spring elementconnecting together two relatively movable members, comprising a casingadapted to be secured to one of said members, a rock shaft in saidcasing having an operative connection with the other of said members, acylinder having an annular flange received in threaded engagement withsaid casing, said flange dividing the casing into two chambers, aninelastic fluid in said chambers, a series of ports in said flange, avalve normally closing said ports, a plunger operable in said cylinderfor circulating the fluid between said chambers, means constantly urgingsaid plunger in a direction towards said rock shaft, a cam on one end ofthe plunger engageable with means on said rock shaft, and thecylindersupporting portion of said casing being adapted for relativerotation to effect adjustment of said valve mechanism, whereby the forcerequired to return said plunger to normal position, will neutralize thereactive force stored in said spring element.

10. In combination with a vehicle including body and axle members havinga yielding connection between them, a casing adapted to be secured toone of said members, said casing comprising an upper relatively fixedsection and a lower section adj ustably secured thereto, a rock shaftinsaid upper section having an operative connection with the other of saidmovable members, a cylinder mounted in the lower casing section andhaving an annular flange suitably secured thereto, a plunger operable insaid cylinder and cooperating with said cylinder flange to divide thecasing into two chambers, an inelastic fluid therein, a high pressurevalve sleeve slidably mounted upon said cylinder and having one end ofa. spring engaged therewith, an adjusting ring received in threadedengagement with one end of the cylinder and slidably and non-rotatablyconnected with the upper casing section, means on said rock shaftengageable with one end of the plunger to return the latter to normalposition, upon return movement of said movable members from abnormalpositions, and said lowercasing section being adapted for rotativemovement to relatively adjust said adjusting ring upon the cylinder tovary the tension of said valve spring, whereby the circulationof thefluid in one direction may be controlled to cause the force required toreturn said plunger to normal position, to substantially neutralize thereactive force stored in said spring element.

11. In combination with a vehicle including body and axle members havinga yielding connection between them, a device adapted to resist returnmovement of. said members after deflection away from a normal relativeposition, said device comprising a casing adapted to be secured to oneof said members, a rock shaft in said casing having an operativeconnect-ion with the other of said members, fluid chambers in saidcasing, an inelastic fluid therein, a valve mechanism between saidchambers, a plunger for circulating the fluid between the chambers,means on said rock shaft to cause said plunger to be actuated when saidshaftis rocked, and a portion of said casing being relatively movableand connected with said valve mechanism, whereby when said movableportion is relatively moved upon the fixed portion of said, casing, saidvalve mechanism will be adjusted.

In witness whereof, we have hereunto set our hands this 12th day ofNovember, 1927.

GROSVENOR M. CROSS. RODERIC M. GROSS.

